This invention relates generally to improved electrical connectors for mounting integrated circuit devices to circuit boards and the like and, more particularly, to electrical connectors having improved covers for pressing the substrates on which the integrated circuit devices are mounted against electrical contacts of the connectors in a manner and with sufficient force to insure good electrical connection between the contacts and conductive pads on the substrate, the pads being electrically coupled to the integrated circuit devices.
Integrated circuit semiconductors, or "chips", as they are often called, are relatively fragile devices which are commonly mounted upon an insulator base. In one common construction, a plurality of relatively thin electrical connector leads project from the base to provide for connection of the device to external circuits. Lead breakage resulting during manufacture and installation or removal of such devices due to the fragile nature of the leads, however, mitigates against their use in many applications, especially in view of their cost.
This problem has been alleviated to a great extent by more recent structures in which the leads are eliminated. In one such structure, the integrated circuit chip is mounted upon a thin, flat, insulator substrate and electrically connected to a plurality of conductive pads provided on the substrate surface immediately adjacent the edges thereof by conductive paths on the substrate. The substrate, in turn, mounts in an electrical connector which serves to connect the integrated circuit device to external circuits on, for example, a printed circuit board.
One type of electrical connector for mounting and electrically connecting an integrated circuit device mounted on a substrate to external circuits is disclosed in U.S. Pat. No. 3,771,109, issued Nov. 6, 1973, to Richard Bruckner, et al., and assigned to Bunker Ramo Corporation, Oak Brook, Ill., the assignee of the present invention. In this and similar prior connectors, the integrated circuit device is initially positioned in an insulator base and then secured therein by a rigid insulator cover. The base includes a plurality of individual metal contacts, one for each conductor pad on the integrated circuit device substrate. These electrical contacts extend above the surface of an interior shoulder in which the contacts are located in contact cavities. When the integrated circuit device is positioned in the base and the cover is closed, the electrical contacts extend from their respective cavities to engage and make electrical contact with the conductive pads and to hold the substrate against the cover, away from the shoulder provided in the base.
The force with which each of the electrical contacts presses against the corresponding conductive pad on the integrated circuit device substrate may vary widely in some connectors due to manufacturing tolerances of the contacts as well as variations in the thickness of the substrate within specified tolerances. This, in turn, may result in less than satisfactory electrical connection between one or more contacts and their corresponding pads and affect the operation of the integrated circuit device.
Moreover, these connectors commonly require at least some tools for mounting or removing an integrated circuit device from the connector.